Stencil sheet



Patented Sept. 24, 1929 UNITED STATES SHINJIRO E0311, TOKYO, J' AIANSTENCIL SHEET.

No Drawing. Application filed December 31, 1927, Serial No. 2441,04 7,and in Japan December8, 1927.

My invention relates to improvements in stencil sheets for use induplicating manuscript and typewritten documents, drawings and the like,consisting of a sheet of fibrous 5 material coated or impregnated'with acoating material which is impermeable to ink and can be stencilized bythe pressure of a writing stylus or the impact of the type of a typewriting machine. 7

It has previously been proposed to produce a stencil sheet of this kindconsisting of a fibrous base coated with a solution of a celluloseester, such as cellulose acetate or nitrate, in a suitable solvent,combining therewith a tempering agent, such as castor oil or a heavyhydrocarbon oil. It has further been proposed to produce a stencil sheetof a fibrous base coated with a solution of esters of polysaccharides ina volatile solvent, combining with a tempering agent, such as naphthenicacid glycerides or chlorinated naphthalene.

The stencil sheet according to the present invention comprises a fibrousbase coated or 2 impregnated with a coating material consisting of asolution of esters of polysaccharides and quince oil.

Quince oil is obtained from the seeds of the quince, Og dom'd oulgm'is,Pers, or Pymc Japom'ca (cultivated in Asia and Europe).

Quince oil is miscible with a solution of esters of polysaccharides, andthe mixture .remains a homogeneous and flexible coating on the basematerial after the evaporation of the solvent.

The present invention is an improvement on. my earlier inventiondescribed in Patent No. 1,587,954, of June 8, 1926, in that it producesa stencil sheet having a coating of the desired softness but withoutstickiness.

I have found that while naphthenic acid glycerides acts as aplastifyingagent, the resulting coating is not sufficiently softto'permit the characters to cut through by the light pressure of a type,unless it is rather excessively used. This is duetothe excessive highviscosity of naphthenic acid glycerides. On the contrary, quince oil hasa viscosity lower than that of castor' oil, or-naphthenic acidglycerides thus producing a sheet which, is

softer and more pliable even tho the quince oil is used in comparativelysmall quantities.

The present invention also is an improvement over that described inPatent No. 1,67 9,034 of July 31, 1928, diclosing the use of squalene,which is a hydrocarbon obtained from liver oils of sharks, as asoftening ma-' terial.

Squalene is an unsaturated liquid hydrocarbon, C H and when exposed toair forms a hard skin similar as in the case of ordinary drying oils, sothat when it is used as a coating material it results in certaindrawbacks, the sheet becoming sticky or hard when kept a long timebefore use. Moreover, the source of squalene is not as abundant and itis diiiicult to obtain squalene i in a pure state. rather expensive.

As compared therewith, quince oil is of comparatively low viscosity, andwhen used as a softening agent it forms a homogeneous coating which isstronger and more durable than can be obtained by the use of squalen'eor other hydrocarbon oils. The coated sheet not only is pliable but alsodurable and stable, and is easily stencilized, yielding excellentcopies, and, moreover, it is unaffected by climatic conditions and maybe kept for a long period of time.

In the carrying out of the invention, a sheet of fibrous base, such asJapanese yoshinopaper, is coated or impregnated'with a coating materialprepared b dissolving esters of polysaccharides, suc as starch acetate,mannan acetate, cellulose acetate, cellulose nitrate, in any suitablesolvents, such as acetone, ethyl alcohol, butyl alcohol, amyl acetate,ethyl acetate, benzol, toluol,

Consequently its use is petroleum benzine or a mixture of them, and Pmixing therewith quince oil. If desired, a suitable quantity of atempering agent, such as natural or artificial resins, fatty acids,naphthenic acid, oils, blown oils, polymerized oils, fats, waxes,glycerin esters, or glycol esters of fatty acids, naphthenic acidglycerides, solid hydrocarbons, chlorinated naphthalene, methyl or ethylphthalate, butyl phtha1ate,butyl stearate, butyl tartrate, triphenyl ortricres'yl phosphate, or a mixture of them, may be added to the abovecoating material. The coating material may also be added into the paperstuff in a mixing hollander during the paper making operation.

The proportions of ,the ingredients of the coating material may varyaccording to several circumstances. The following is an example Parts byweight Cellulose nitrate 10 Acetone 20 Ethyl alcohol. 20 Ethyl acetate20 Amyl acetate 40 Benzol 20' Quince oil 20 Oleine 5 Stearine L 5 Theterm esters of polysaccharides'is intended to include not only one ofdefinite esters of polysaccharides, but also a mixture of them.

What I claim is 1. A stencil sheet consisting of a base of fibrousmaterial and a coating including esters of polysaccharides and quinceoil.

2. A stencil sheet consisting of a base of fibrous material anda'coating including esters of polysaccharides, quince oil and temperingagents.

In testimony whereof I aflix my si ature.

SHINJIRO H RII.

